Unexpected 'Norinjae Warning' in Japan... Excessive Breeding Due to Abnormal High Temperatures

Damage to Houses and Farms and Repeated Complaints
Mass Breeding in Summer... Increased Activity Due to High Temperatures in November

As South Korea faces an emergency in pest control due to the appearance of bedbugs, Japan is dealing with a problem caused by an overpopulation of stink bugs due to abnormal high temperatures. Normally, stink bugs should be preparing for winter hibernation, but the high temperatures have allowed them to remain active even in late autumn, increasing the damage.

On the 9th, TBS and the Asahi Shimbun reported that this summer, stink bugs have bred massively nationwide in Japan, and they continue to be active even in November, when they should be entering hibernation, causing inconvenience to citizens.

Stink bugs attached to the windows of a private house. (Photo by TBS)

Stink bugs usually start preparing for hibernation from late October, so they are insects not seen during winter. They prefer warm places, so when temperatures drop from late October, they often seek out houses with relatively higher temperatures. They are generally known to enter houses or farms near mountainous villages and cause damage.

However, due to the abnormal high temperatures continuing since this summer, stink bugs have started to be active even in large cities such as Osaka. Dozens of stink bugs have been seen flying around street lamps in parks within Kyoto city, and reports have been made daily of stink bugs getting into socks hung out to dry at ordinary households or sticking to walls and windows.

Moreover, when provoked, they emit a foul odor as a defense mechanism, making it difficult to catch them carelessly. This has led to ongoing discomfort among residents due to the smell.

Stink bugs that entered through the gaps in the house windows. (Photo by TBS)

TBS reported on the case of villagers living at the foot of mountains in Tottori Prefecture. Hundreds of stink bugs attach themselves daily to window screens and clothing, forcing residents to keep box tape on hand to remove the bugs from their clothes throughout the day.

Damage to farms is also continuing. In a persimmon orchard in Wakayama Prefecture, stink bugs have eaten the fruit, causing the surface to turn black or leaving scratches on the crops, prompting emergency pest control measures.

In response, the Ministry of Agriculture, Forestry and Fisheries issued a stink bug warning in September to 21 local governments nationwide, including Kyoto and Wakayama Prefectures, urging thorough crop management. However, with stink bugs expected to remain rampant until mid-November, it has become difficult to lower vigilance.

A persimmon discolored due to stink bugs. (Photo by NHK)

Experts analyze that this massive breeding is due to abnormal high temperatures caused by global warming. As global warming continues to cause high temperatures, the hot summers favored by stink bugs have persisted, leading to overpopulation. Additionally, although it is the time to find a place to hibernate, the unprecedented high temperatures continuing into November have caused them to keep flying around in search of a place to settle, according to experts. In fact, Tokyo’s daytime temperature rose to as high as 26 degrees Celsius on the 4th.

A representative from the Tottori Prefectural Museum explained, "November is the time when stink bugs look for the optimal place to spend the winter," adding, "They can fly well only when the weather is warm, so they seem to be moving more actively to find a hibernation spot."

Furthermore, city lights also stimulate stink bugs. A representative from the Itami City Insect Museum in Hyogo Prefecture said, "Stink bugs have a strong tendency to approach lights, so they stick to entrances or windows," advising TBS, "If disturbed, they emit a smell, so it is important not to provoke them by wrapping them in tissue or placing them in a PET bottle and releasing them outdoors."

This content was produced with the assistance of AI translation services.